Hong Kong -LRB- CNN -RRB- A daring cross-border raid by one of Russian President Vladimir Putin 's associates has -- so far -- yet to sour Sino-Russian relations .

According to Chinese state media , Ustin , one of three rescued Amur tigers released by the Russian leader earlier this year , has attacked a herd of goats on Heixiazi Island in the northern province of Heilongjiang .

The region shares a border with Russia 's far-eastern Amur region , and it is thought that the tiger crossed the Heilongjiang river to hunt .

Russian conservationists rescued five cubs in 2012 , and the Russian president was on hand for their release following rehabilitation and hunting training .

The animals were fitted with tracking devices and in October , Ustin , along with another released tiger , Kuzya , were found to have made their way to China .

A wildlife protection expert from China 's Northeast Forestry University , Zhu Shibing , said that footprints and other traces left near the goat 's shelter belonged to Ustin .

Chinese news agency Xinhua reported that the skulls of the two dead goats were crushed and had puncture wounds the `` size of a human finger '' -- a testament to the power of the tiger 's bite . Three further goats remain missing .

`` Our monitoring data and this attack all tell that Ustin is in good physical condition , and has a large range of activities on Heixiazi Island , '' Xinhua quoted Zhu as saying .

He also warned villagers to keep their distance , should they spot the goat killer , and to not throw food at it .

Kuzya , the other tiger known to have crossed into China , was previously blamed for an attack on a Chinese hen-house .

The Russian leader has been involved in conservation efforts of the species .

He is often photographed with tigers and other wild animals , and takes part in a number of outdoor activities in an apparent effort to bolster his image as a strong , intrepid leader .

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Tiger released by Russian President Vladimir Putin thought to have attacked goats in China

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Dead goats have ` finger-sized ' holes in their skulls , consistent with a tiger bite

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This is not the first raid blamed on a tiger released by Putin